drugs to treat GERD, PUD, IBD and h.pylori Flashcards
what are the different treatment options for GERD
lifestyle modifications
antacids
surface agents
H2receptor antagonists (H2RAs)
proton pump inhibitors (PPI)
what is the MOA of Antacids
neutralize acid (raise pH)
what are the uses of antacids
mild, intermittent heartburn or reflux (<1 episode/week)
what is the PK of antacids
onset: 5 min
duration: 30-60 minutes
what are the types of Antacids
calcium hydroxide (tums, maalox)
aluminum hydroxide (mylanta, gaviscon)
magnesium hydroxide (mylanta, gaviscon)
what are the SE of calcium hydroxide antacids
constipation
hypercalcemia
alkalosis
acute or chronic renal injury
what are the SE of aluminum hydroxide antacids
constipation
hypophosphatemia
*caustion with renal failure
what are SE of magneisum hydroxide antacids
diarrhea,
hypermagnesemia
*caution with renal failure
what is the MOA of surface agents
coats esophageal/gastric mucosa, creates physical barrier between mucosa and acid
what are the uses of surface agents
short-term management of GERD symptoms (4-8 weeks for duodenal ulcer)
swallow after meals, avoid drinking/eating afterwards
what is the PK of surface agents
onset: 5 minutes
duration: 30-60 minutes
what are the types of surface agents
sucralfate
sodium alginate
bismuth
what are the SE of sucralfate
constipation
aluminum toxicity
*caution with: renal failure, DM
What is the MOA of H2RAs
blocks stimulation of gastric parietal cells by competing with histamine H2 receptor
what are the uses of H2RAs
GERD, dyspepsia, PUD
-less effective than PPI, may be useful as adjunct
-not effective for H/pylori
what is the PK of H2RAs
onset: 2 hours
Duration: 4-10 hours
what are H2RA durgs
cimetidine, famotidine
what are the SE of H2RAs
HA, dizziness, diarrhea, constipation
cimetidine: gynecomastia
prolonged use(>2yrs) may lead to B12 deficiency
what is the MOA of PPIs
block gastric H/K-ATPase, inhibiting gastric acid secretion
what is the uses of PPIs
GERD, dyspepsia, PUD, H.pylori
-most effective acid suppressing med
what is the PK of PPIs
onset: 1 hour
duration: ~24 hours
admin: 30-60 min before first meal of the day
what are the PPI medications
Omeprazole
Pantroprazole
Lansoprazole
Esomeprazole
what are the risks of PPIs
available for >25 yo. may double blinded RCTs over years have not supported initial safety concerns
longer term: malabsorption of some minerals and vitamins, increased risk of some diarrheal illnesses, bacterial pneumonia, acute interstitial nephritis (AIN), CKD, gastric polyps
what are the SE of PPIs
HA
nausea
abdominal pain
diarrhea
what are drug interactions with PPIs
decreased absorption of certain HIV protease inhibitors
increased concentration of digoxin, carbamazepine, theophylline; warfarin, diazepam, phenytoin
Increased MTX concentration/toxicity
decrease anti-platelet effect of Plavix
decrease absorption of PO iron
what is the Tx of PUD
avoid offending agents
anti-seretory agent (PPI) = mainstay of tx
test for and treat h.pylori if present
what is the tx regimen for H/pylori
2 week duration
Triple therapy: Clarithromycin + amoxicillin + PPI
Quadruple therapy: bismuth subsalicylate + tetracycline + metronidazole + PPI
what is the MOA for Busmuth
stimulates prostaglandin/mucous/bicarb production in the stomach
mild antimicrobial activity, specifically against H.pylori
reduces inflammation